El Niño May Increase Coastal Flood Risk in California
A new report released Wednesday by the National Oceanic and Atmospheric Administration predicts coastal cities in California could experience more days of coastal flooding this winter because of the developing El Niño weather pattern.
El Niño occurs during a periodic warming of waters in the equatorial Pacific Ocean. This causes the jet stream to shift, altering where major storms strike the United States.
The El Niño currently developing appears to be one of the strongest ever recorded, based on the degree of temperature change in the ocean. Many media outlets have mistakenly reported that this will end California’s drought, because the state will see more storms as a result.
In reality, the result will hinge on where those storms strike the state, which can’t be predicted. Even so, communities throughout the state are busily preparing for a stormy winter — so busy that some roofers and tree trimmers have reportedly stopped accepting new jobs.
The new NOAA study looks at historical coastal flooding patterns that occur during El Niño conditions as a result of storm surge and tidal fluctuations. The study adds in the effects of climate change and sea-level rise to predict how often coastal cities will see so-called “nuisance” flooding, or conditions that inconvenience the public.
The study looks at locations nationwide, and only two places in California are included: San Francisco and La Jolla. The results show that San Francisco could see 21 days of coastal flooding this winter. That’s nine more days, or a 75 percent increase, thanks to El Niño. Lo Jolla in the San Diego area could see 10 days of coastal flooding, a 67 percent increase.
“We know that nuisance flooding is happening more often because of rising sea levels, but it is important to recognize that weather and ocean patterns brought on by El Niño can compound this trend,” William Sweet, the NOAA scientist who led the study, said in a statement.
On Thursday, NOAA released an updated El Niño forecast that reiterates the weather phenomenon will be “strong” this coming winter. In response, California’s state climatologist Michael Anderson released a statement urging people not to expect any water supply miracles from El Nino.
“Current El Niño conditions cannot tell us how many storms may cross California this coming winter or how much rain and snow will fall in our state,” Anderson said.
Low Flows: Documenting the Drought’s Effect on Streams
The U.S. Geological Survey is in the midst of a study to document stream conditions across the West to understand how severe drought affects the environment.
“This year’s warmer, drier weather provides a preview of how future droughts may impact water resources in the study area,” said Chris Konrad, USGS hydrologist and study project chief. “The goal is to provide information to resource managers to help understand differences in how streams respond to drought and plan for future drought impacts throughout the region.”
The team is collecting stream flow and temperature data from some 500 streams across six states, including California. Scientists will then compare those data with measurements from previous years to answer several water-management questions, such as which streams are most vulnerable, and whether 2015 can serve as a model for future climate change conditions. The data will be compiled and analyzed for a report expected in late 2016.
“The streamflow data will be important for future drought planning and resource management decisions throughout the western United States,” said Rich Ferrero, USGS Northwest Regional Director.
Celebrating a “Drought-Proof” Marijuana Crop
Marijuana growers and their fans will gather in Humboldt County on Saturday for the “Golden Tarp Awards,” an event that celebrates so-called “light dep” marijuana.
Light dep stands for “light deprivation.” Farmers use tarps to cover their marijuana plants to trick the crop into thinking that fall has arrived early. This causes the plants to produce their treasured buds earlier and in a more potent form.
The benefits are not only a better product but also lower water consumption. Because the plants peak earlier than they would without the tarps, the bud harvest can begin earlier and several weeks of additional irrigation are not necessary.
The process avoids water takings during peak drought season in the late summer and fall.
“It allows you to work when water levels are highest,” Kevin Jodrey, founder of the Golden Tarp Awards, told the San Francisco Chronicle.
Top photo: Cyclists cross a flooded path in Marin County during a high tide in December 2014. A new study by the National Oceanic and Atmospheric Administration says California coastal areas could see more conditions like this in the upcoming winter, in part because of a strong El Niño that is forecasted. (Jef Poskanzer, California King Tides Photo Initiative)